Shear behaviour of Canadian marine clay/geomembrane interface under freeze–thaw cycles

Abstract

The influence of the number of freeze-thaw (F-T) cycles on the interface shear behaviour of a compacted marine clay (Leda clay)/smooth high-density polyethylene (HDPE) geomembrane is investigated in this paper. Shear tests are performed on samples subjected to various numbers of F-T cycles: zero, one, two, three, five and ten. The test results show that the interface shear strength of the Leda clay/smooth HDPE geomembrane is lower than that of Leda clay. The interface shear strength of the Leda clay/smooth HDPE geomembrane decreases with increasing number of F-T cycles. Furthermore, the interface shear friction angles of the Leda clay/smooth HDPE geomembrane are significantly reduced within the first three F-T cycles. The reduction in strength beyond the three F-T cycles is negligible. The total decrease in the shear strength of the samples that are not subjected to an F-T cycle compared to that of samples subjected to ten F-T cycles is 18 center dot 3, 17 center dot 6 and 13 center dot 6% under a vertical stress of 150, 250 and 350 kPa, respectively.